'use strict';

function get_letter_interval(number_a, number_b) {
  //在这里写入代码
   return two_numTurnArray(number_a,number_b).map((item)=>{
    return item = String.fromCharCode(item + 96) ;
  }) ;
  
}
module.exports = get_letter_interval;
  

function two_numTurnArray(number_a,number_b){
  let arr1 = [] ;
  //不相等
  if(number_a > number_b){
    for(let value = number_a ;value >= number_b ; value --){
      arr1.push(value) ;
    }
  }
  if(number_a < number_b){
    for(let value = number_a ;value <= number_b ; value ++){
      arr1.push(value) ;
    }
  }
  //相等情况
  if ((number_a === number_b)) {
      arr1.push(number_a) ;
    }
    return arr1 ;
}
// console.log(two_numTurnArray(1,5));
// console.log(two_numTurnArray(5,1));
// console.log(two_numTurnArray(5,5));
// console.log(get_letter_interval(1,5));
